18.6 IEC 60870-5-103 communication protocol IP14615-1 v218.6.1 Application IP14864-1 v1M17109-3 v7TCP/IPControl CenterIED IEDIEDGatewayStar couplerStation HSIIEC05000660-4-en.vsdIEC05000660 V4 EN-USFigure 162: Example of IEC 60870-5-103 communication structure for asubstation automation systemIEC 60870-5-103 communication protocol is mainly used when a protection IEDcommunicates with a third party control or monitoring system. This system musthave software that can interpret the IEC 60870-5-103 communication messages.When communicating locally in the station using a Personal Computer (PC) or aRemote Terminal Unit (RTU) connected to the Communication and processingmodule, the only hardware needed is optical fibers and an opto/electrical converterfor the PC/RTU, or a RS-485 connection depending on the used IEDcommunication interface.18.6.1.1 Functionality M17109-38 v3IEC 60870-5-103 is an unbalanced (master-slave) protocol for coded-bit serialcommunication exchanging information with a control system. In IEC terminologya primary station is a master and a secondary station is a slave. The communicationis based on a point-to-point principle. The master must have software that caninterpret the IEC 60870-5-103 communication messages. For detailed informationabout IEC 60870-5-103, refer to IEC 60870 standard part 5: TransmissionSection 18 1MRK 505 393-UEN BStation communication384 Line differential protection RED650 2.2 IECApplication manual
